Dental instrument



Feb. H8, 11936. F. F. MARSCHALK DENTAL INSTRUMENT Filed Nov. 5, 1954 Inventor 7. F MdmschaZ/r Patented Feb. 1 8, 1936 UNITED STATES eATENT OFFICE 3 Claims.

My invention relates generally to dental instruments, and particularly to a dental tool for carrying cavity filling material to the cavity to be filled and for packing the material in the bottom of the cavity, and an important object of the invention'is to provide a tool of the character indicated which is simple and efiicient and enables the operator to deposit and pack either large or small quantities of the filling material in the cavity at his discretion so as to enable easily building restoration in the cavity according to the best methods.

Another important object of my invention is to provide a tool of the character indicated above which is delicate enough in action to enable properly condensing a filling from the bottom'of the cavity.

Another important object of my invention is to provide a tool of the character indicated above which is so arranged that the operator has a clear view of the working edge and of the shank of the tool while working within the cavity.

Other important objects of my invention are to provide a tool of the character indicated above which involves automatic discharge of the filling material carried into the cavity, which involves retractile filling material carrying means, which is retractible so as to give a clear View of the shank and the working edge of the tool, which has an adequately small packer edge, and which has the proper contra-angle.

Other objects and advantages of my invention will be apparent from a reading of the following description in connection with the accompanying drawing wherein for purposes of illustration I have shown a preferred embodiment of my invention.

In the drawing:

Figure 1 is an elevational view of one side of the embodiment showing a portion thereof broken away and a portion in longitudinal vertical cross section for the purpose of disclosing the arrangement of the interior mechanism.

Figure 2 is a perspective view of the carriage.

Figure 3 is a perspective view of the carriage retracting arm.

Figure 4 is a perspective view of the notched packing tip.

Referring in detail to the drawing, the numeral 5 generally designates the instrument or tool which comprises the outer tubular cylinder 6 having the conical cap I closing one end and having at its tip the shank 8 which is bent to ward one side as indicated at 9 and has on its outer end substantially a goose neck Ill containing the packing tip I I which has on its outer side a notch l2.

The conical head I is threaded into the end of the cylinder 6 as indicated at I3 and has a longitudinal side opening It through which the car- 5 riage operating arm I5 works. The head I! forms an abutment for one end of the helical spring I6 which lies within the cylinder 6 and has its opposite end connected with the plunger I! in which the inner end of the operating rod I5 is an- 10 chored as indicated at I8. The dotted lines in Figure 1 illustrate the in-pushed position of the plunger II and the extended position of the operating rod l5 and the extended position of the carriage I9. As shown in Figure 1 the operating rod I5 is located within the coils of the spring The operating rod I5 comprises the straight bar element 29 which has its inner end deflected as indicated at 2| and its opposite end deflected 20 as indicated at 22, said outer end having on its I extremity the U-shaped yoke 23 the outer extremity of whose arms have pivot receiving holes 24 to receive the pivot 25 which connects the arms on the opposite sides of the boss 26 which is traversed by the pivot 25, so that the operating rod is connected to the carriage I9.

The carriage I9 is semi-cylindrical in cross section and has the boss 26 on the back thereof near one end, and the carriage slides along the packing tip ll, along the back of the gooseneck part l0, and along the back of the shank 8 into the position shown in full lines in Figure l in the retracted position of the tool.

In the extended position of the tool with the parts arranged as shown in dotted lines in Figure 1, the carriage I9 embraces the packing tip I I and extends therebeyond so that there is provided between the outer end of the carriage and the extremity of the tip I I a pocket in which the amalgam or other cavity filling material is placed so as to be carried to and placed into the cavity of the tooth being operated upon. In the dotted line position of the carriage shown in Figure 1 the inner end of the carriage engages the notch I2 of the packing tip II so as to be held in the extended or dotted line position. Upon pressing the filling material into place in the cavity, the carriage is dislodged from the notch I2 and the spring it pulls the operating rod I5 to the full line position shown in Figure 1, wherein the carriage is engaged with the shank 8 and completely out of the way of the tip II. The retracting movement of the carriage causes the quantity of filling material in the carriage and at the extremity of the tip I l to be discharged into the cavity as will 'be obvious. The bar portion 20 of the operating rod is sufiiciently springy in character as to cause the carriage to follow along the back of the shank 8, the goose neck portion I and the strip ll during the extending movement thereof caused by pushing in the plunger l1. At the extreme outward position of the operating rod, the arms of the yoke 23 are on opposite sides of the goose neck portion I 0 as indicated in the dotted lines in Figure 1, while the carriage extends along and around the tip II and projects therebeyond to define with the extremity of the tip II the pocket in which the amalgam or other filling material is located and carried.

In resetting the instrument pressure is placed on the operating rod l exposed in the opening M in the tip part of the handle. The dotted lines in Figure 1 show the carriage ready to engage the amalgam or other filling material and to carry the same to the cavity. The packing of the filling is done while the parts are in their retracted full line positions shown in Figure 1.

Although I have shown and described herein a preferred embodiment of my invention, it is to be definitely understood that I do not desire to limit the application of the invention thereto, and any change or changes may be made in the materials, and in the structure and arrangement of the parts, within the spirit of the invention and scope of the subjoined claims.

Having thus described my invention, what I claim as new is:

1. An instrument of the character described comprising a handle, an operating member longitudinally movable therein, said handle having a packing tip, a carriage slidable on said tip and connected to said operating member, said operating member being adapted to be extended to place said carriage along the extremity of said tip so as to cause said carriage to define with said tip a filling material receptacle, said operating member being arranged to be retracted to deposit the filling material into a cavity and retract said carriage from said tip so as to leave the tip free for operating upon the filling material within the cavity.

2. An instrument of the character described comprising a handle, an operating member longitudinally movable therein, said handle having a packing tip, a carriage slidable on said tip and connected to said operating member, said operating member being adapted to be extended to place said carriage along the extremity of said tip so as to cause said carriage to define with said tip a filling material receptacle, said operating member being arranged to be retracted to deposit the filling material in a cavity and retract said carriage from said tip so as to leave the tip free for operating upon the filling material within the cavity, said handle including spring means for retracting said operating member.

3. In combination with a dental instrument including a handle, a shank and a packing tip extending at substantially right angles to the shank, a carriage of elongated form and of substantially semi-cylindrical shape in cross section, an operating member carried by the handle, a rod connected with the operating member and pivotally connected with the carriage, said operating member when moved toward the shank causing the rod to move the carriage over the shank and along the tip to a position where the carriage projects slightly beyond the tip, said tip having a notch therein for engagement by the rear end of the carriage for holding the carriage in position projecting from the tip, the carriage moving out of engagement with the notch when pressure on the front end of the carriage against a tooth occurs and spring means for retracting the operating member and the rod and carriage to position the carriage on an inner portion of the shank.

FREDERICK F. MARSCHALK. 

